Configurations in which shift maps for determining shift timing can be switched according to a change in a running condition and a rider's intention in a shift control unit of an automatic transmission is hitherto known. Operation for switching the shift maps is arbitrarily performed by a rider and in addition, a technique for automatically switching them based upon output values from various sensors is well-known.
In JP-A No. S63-254257, in a shift control unit provided with a shift map in which fuel economy is emphasized (an economical mode) and a shift map in which engine performance is emphasized (a power mode), it is disclosed that the power mode is selected only when a condition in which an angle of a throttle operated by a rider is equal to or larger than a set angle continuously for fixed time or longer.
However, according to the technique of JP-A No. S63-254257, control over switching the shift maps is made based upon an output signal of a throttle angle sensor and it is expected that optimum control can be made according to the existence of a passenger and/or a cargo.
The object of the invention is to address the above-mentioned problem of the related art and to provide a shift map switching control unit that can switch shift maps of an automatic transmission according to an output signal from a load sensor.